Objective: To estimate the frequency of contrast nephropathy after computed tomography angiography (CTA) to rule out pulmonary embolism (PE) in the emergency department (ED) setting. Methods: We prospectively followed patients undergoing CTA for PE, while in the ED, for 45 days. Patients who refused follow‐up or were receiving hemodialysis were excluded. Severe renal failure was defined as an increase in creatinine ≥ 3.0 mg dL−1 or a need for hemodialysis within the follow‐up period. Patients were also followed for laboratory‐defined contrast nephropathy, defined as an increase in creatinine of > 0.5 mg dL−1 or > 25%, within seven days following CTA. Results: A total of 1224 patients were followed, and 354 [29%, 95% confidence interval (CI): 26–32%] patients had paired (preCTA and post‐CTA) creatinine measurements. None developed renal failure (0/1224; 0%, CI: 0–0.3%). 44 patients developed laboratory‐defined contrast nephropathy, corresponding to an overall frequency of 4% (44/1224; CI: 3–5%) and 12% (44/354; 95% CI: 9–16%) among those with paired creatinine measurements. Conclusions: Following CTA for PE, the incidence of severe renal failure was very low, but the incidence of laboratory‐defined contrast nephropathy (4% overall and 12% of those with paired measurements) was higher than expected.
